1. Field of the Invention
This invention relates to devices for drilling holes in steel safes to gain entry, and more particularly to a drill mounting structure that is magnetically mountable, adjustable, portable and collapsible and designed to provide multiple precise positioning of a drill bit for continuous aligned drilling of a safe having a door or front entrance of any size.
2. Description of the Prior Art
As generally indicated this invention relates to drill mounting structures that magnetically mount to any size steel surface and then position and guide a power drill to a predetermined spot for continuous aligned drilling requirements. The prior art shows a variety of devices with various primary non-magnetic attachment or clamping means limited by the size of the safe or vault. Further the prior art discloses a number of different guiding and holding means for power drills. See, for example U.S. Pat. No. 2,849,900 issued to Heidtman in 1958; U.S. Pat. No. 3,327,573 issued to Prussiano in 1967.
In U.S. Pat. No. 2,849,900, a portable frame for a power drill is shown having a drill holder that can be aligned relative to a cylindrical object with adjustments of 180.degree. in relation to the object. In U.S. Pat. No. 3,327,573 a door lock and drilling guide is disclosed that can move a drill and template vertically and horizontally in relation to the edge of the door. The new and novel device is adapted for use on steel safes having any size door without the necessity to clamp the device to a plurality of proximate edges. Yet, the novel device meets all state of the art requirements for the accurate positioning of a drill on a safe by an adjustable frame and the requirement for continuous pressure on the drill to maintain cutting efficiency because force provided by the magnetic clamps and clamping arrangement vastly exceeds the force necessary to maintain cutting efficiency for even the most hardened, state of the art steel safe doors.
Other relevant patents include U.S. Pat. No. 3,884,592 issued to Shulters in 1975 for a portable center drill; U.S. Pat. No. 4,197,041 issued to Prewitt in 1980 for a boring tool; U.S. Pat. No. 4,307,983 issued to Blough et al. in 1981 for an apparatus for gaining access to enclosures secured by cylinder lock by boring a hole therein; U.S. Pat. No. 4,533,284 issued to Agius et al. in 1985 for an adjustable mounting device for drilling a safe which frictionally attaches to edge of the safe or has destructive attachment holes drilled therein; U.S. Pat. No. 4,714,386 issued to Phillips for an apparatus for drilling a repairable access hole in a safe using a frictionally mounted derrick; U.S. Pat. No. 4,865,493 was issued to Miller in 1989 for a derrick attached to a safe for drilling same; U.S. Pat. No. 4,932,814 was issued to York in 1990 for a portable line boring machine; and U.S. Pat. No. 4,978,257 was issued to Nowman for a frictionally attachable safe drilling rig.
The prior art has not recognized the advances in industrial magnets and their application in providing a quick and economical solution to the drilling rig attachment problem and the solution to the problem arising from meeting the need to quickly and non-destructively attach a drilling rig to very large safes.